1// Copyright (c) 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CHROME_BROWSER_EXTENSIONS_API_AUDIO_AUDIO_SERVICE_H_
6#define CHROME_BROWSER_EXTENSIONS_API_AUDIO_AUDIO_SERVICE_H_
7
8#include "base/basictypes.h"
9#include "base/callback.h"
10#include "chrome/common/extensions/api/audio.h"
11
12namespace extensions {
13
14typedef std::vector<linked_ptr<api::audio::OutputDeviceInfo> > OutputInfo;
15typedef std::vector<linked_ptr<api::audio::InputDeviceInfo> > InputInfo;
16typedef std::vector<std::string> DeviceIdList;
17
18class AudioService {
19 public:
20  class Observer {
21   public:
22    // Called when anything changes to the audio device configuration.
23    virtual void OnDeviceChanged() = 0;
24
25   protected:
26    virtual ~Observer() {}
27  };
28
29  // Callback type for completing to get audio device information.
30  typedef base::Callback<void(const OutputInfo&, const InputInfo&, bool)>
31      GetInfoCallback;
32
33  // Creates a platform-specific AudioService instance.
34  static AudioService* CreateInstance();
35
36  virtual ~AudioService() {}
37
38  // Called by listeners to this service to add/remove themselves as observers.
39  virtual void AddObserver(Observer* observer) = 0;
40  virtual void RemoveObserver(Observer* observer) = 0;
41
42  // Start to query audio device information. Should be called on UI thread.
43  // The |callback| will be invoked once the query is completed.
44  virtual void StartGetInfo(const GetInfoCallback& callback) = 0;
45
46  // Set the devices in the following list as active. This will only pick
47  // the first input and first active devices to set to active.
48  virtual void SetActiveDevices(const DeviceIdList& device_list) = 0;
49
50  // Set the muted and volume/gain properties of a device.
51  virtual bool SetDeviceProperties(const std::string& device_id,
52                                   bool muted,
53                                   int volume,
54                                   int gain) = 0;
55
56 protected:
57  AudioService() {}
58
59  DISALLOW_COPY_AND_ASSIGN(AudioService);
60};
61
62
63}  // namespace extensions
64
65#endif  // CHROME_BROWSER_EXTENSIONS_API_AUDIO_AUDIO_SERVICE_H_
66